MC

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

As the pressure on the surface of a liquid decreases, the temperature at which the liquid will boil:

a.  decreases

b.  increases

c.  remains the same

 

Correct Answer: a

 

 

 

MC

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

As a solute is added to a solvent, what happens to the freezing point and the boiling point of the solution?

a.  The freezing point decreases and the boiling point decreases.

b.  The freezing point decreases and the boiling point increases.

c.  The freezing point increases and the boiling point decreases.

d.  The freezing point increases and the boiling point increases.

 

Correct Answer: b

 

MC

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

A 2.0 molal sugar solution has approximately the same freezing point as a 1.0 molal solution of

a.  CaCl2

b.  CH3COOH

c.  C2H5OH

d.  NaCl

 

Correct Answer: d

 

MC

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

Which aqueous solution has the lowest freezing point?

a.  1.0 M C6H12O6

b.  1.0 M C2H5OH

c.  1.0 M CH3COOH

d.  1.0 M NaCl

 

Correct Answer: d

 

 

 

 

 

 

MC

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

What occurs when NaC1(s) is added to water?

a.  The boiling point of the solution increases, and the freezing point of the solution decreases.

b.  The boiling point of the solution increases, and the freezing point of the solution increases.

c.  The boiling point of the solution decreases, and the freezing point of the solution decreases.

d.  The boiling point of the solution decreases, and the freezing point of the solution increases.

 

Correct Answer: a

 

MC

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

1. A student has two water solutions containing sugar. Solution "A" has 10 grams of sugar dissolved in 100 milliliters of water. Solution "B" has 25 grams of sugar dissolved in 100 milliliters of water. Which prediction concerning the freezing and boiling points of these solutions is correct?

a.  The boiling point and freezing point of Solution "A" would be lower than Solution "B".

b.  The boiling point and freezing point of Solution "B" would be lower than Solution "A".

c.  The boiling point of Solution "A" would be lower than Solution "B", and the freezing point of Solution "B" would be lower than Solution "A".

d.  The boiling point of Solution "B" would be lower than Solution "A", and the freezing point of Solution "A" would be lower than Solution "B".

e.  The boiling point and freezing point of Solutions "A" and "B" would be the same.

 

 

 

 

 

 

 

 

 

 

2. A student has two water solutions containing sugar. Solution "A" has 1 5 grams of sugar dissolved in 100 milliliters of water. Solution "B" has 5 grams of sugar dissolved in 100 milliliters of water. Which prediction concerning the freezing and boiling points of these solutions is correct?

a.  The boiling point and freezing point of Solution "A" would be lower than Solution "B".

b.  The boiling point and freezing point of Solution "B" would be lower than Solution "A".

c.  The boiling point of Solution "A" would be lower than Solution "B", and the freezing point of Solution "B" would be lower than Solution "A".

d.  The boiling point of Solution "B" would be lower than Solution "A", and the freezing point of Solution "A" would be lower than Solution "B".

e.  The boiling point and freezing point of Solutions "A" and "B" would be the same.

 

Correct Answers:

1.  c

2.  d

 

MC

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

1. Benzene is not soluble in water. The normal freezing point of benzene is 5.5ÁC. The normal freezing point of water is 0.0ÁC. What would the freezing point of water be if 10 milliliters of water were mixed with 10 milliliters of benzene?

a.  5.5ÁC

b.  2.75ÁC

c.  0.0ÁC

d.  2.75ÁC

e.  5.5ÁC

 

2. Chloroform is not soluble in water. The normal freezing point of chloroform is 63.5ÁC. The normal freezing point of water is 0.0ÁC. What would the freezing point of water be if 10 milliliters of water were mixed with 10 milliliters of chloroform?

a.  63.5ÁC

b.  31.75ÁC

c.  0.0ÁC

d.  31.75ÁC

e.  63.5ÁC

 

Correct Answers:

1.  c

2.  c

 

 

MC

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

Why is salt applied to roads to melt ice in the winter?

a.  Car tires grind the salt crystals into the ice, breaking the ice apart and causing it to melt.

b.  Sunlight is refracted through the salt crystals, creating intense beams of sunlight on the ice, causing it to melt.

c.  The salt crystals absorb solar energy more efficiently than ice, creating warm spots on the surface of the ice, causing it to melt.

d.  The salt dissolves into the ice, depressing the freezing point of the ice, causing it to melt.

e.  Heat is released when the salt dissolves in the ice, causing it to melt.

 

Correct Answer: d

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

I

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

Jos³ wanted to investigate how dissolving a substance in water would affect the freezing point of water. He chose to work with acetic acid because it is soluble in water at any concentration and has a density very similar to water (1.05 g/mL). He mixed different concentrations of acetic acid and water by varying the percentage volume of acetic acid present. for example, 10 mL (milliliters) of acetic acid mixed with enough water to make 100 mL would yield a 90% water solution. He then determined the freezing points and densities of each of the solutions and graphed his results:

 

1. What is the approximate normal freezing point of acetic acid?

a.  20ÁC

b.  0ÁC

c.  -5ÁC

d.  -35ÁC

e.  Cannot be determined from the supplied information.

 

2. What is an appropriate conclusion for the results of this experiment?

a.  Density of a water solution is directly proportional to the freezing point of the solution.

b.  Density of a water solution is indirectly proportional to the freezing point of the solution.

c.  The lowest freezing point of a water solution will occur when the density is half‑way between the densities for 100% and 0% water solutions.

d.  The lowest freezing point of a water solution will occur where water is still a solvent and not yet a solute in the solution.

e.  The freezing point of a water solution must be determined experimentally, it is too difficult to make a generalization about this experiment.

 

Correct Answers:

1.  a

2.  d

 

I

Chemistry

Standard: 06

Objective: 02. Summarize affects of colligative properties on a solution when solute is added.

ILO:

 

 

Jos³ wanted to investigate how dissolving a substance in cyclohexane would affect the freezing point of cyclohexane (density = 0.8 g/mL). He chose to work with phenol because it is soluble in cyclohexane at any concentration and has a density very similar to cyclohexane (0.9 g/mL). he mixed different concentrations of phenol and cyclohexane by varying the percentage volume of phenol present. for example, 10 mL (milliliters) of phenol mixed with enough cyclohexane to make 100 mL would yield a 90% cyclohexane solution. He then determined the freezing points and densities of each of the solutions and graphed his results:

 

 

1. What is the approximate normal freezing point of phenol?

a.  40ÁC

b.  10ÁC

c.  -5ÁC

d.  -20ÁC

e.  Cannot be determined from the supplied information.

 

2. What is an appropriate conclusion for the results of this experiment?

a.  Density of a cyclohexane is directly proportional to the freezing point of the solution.

b.  Density of a cyclohexane solution is indirectly proportional to the freezing point of the solution.

c.  The lowest freezing point of the cyclohexane solution will occur where cyclohexane is still a solvent and not yet a solute in the solution.

d.  The lowest freezing point of a cyclohexane solution will occur when the density is less than half-way between the densities for 100% and 0% cyclohexane solutions.

e.  The freezing point of a cyclohexane solution must be determined experimentally, it is too difficult to make a generalization about this experiment.

 

Correct Answers:

1.  a

2.  c